Toroids and MOSFETs and firmware, oh my! (aka:'Tiny13+N-FET=???')

What work together - the 7135's and FET's? You, from the firmware, control which output circuit you want to use - 7135 or FET's. It's two different circuits, throw a switch in the firmware (turbo ON or OFF), and the board operates as a FET output board, like comfy's here, or it operates like a regular Nanjg 7135 based board -- Best of Both , or actually is both...

Ahh, so if there’s a way to send it up in smoke I’d do it through my programming. I took programming in college. In 1980. Do you know how many times I’ve slept since then?

(Crimey but that makes me feel old! My wife was 4 when I was in college.)
[To clarify, she was 27 when we got married 11 years ago.]

Great info guys. Not sure if Comfy's approach will be harmful to the emitter still, but it's not going to stop me from implementing his approach on some of my lights. It's a great solution for existing drivers that don't do what I want them to do.

That is what the PWM function is for, control the overall power to the emitter, 4.2vdc won't instantly smoke a LED, but it will get HOT fast...if you didn't switch it off and on at varying levels then sure it more than likely would smoke...but this is why the PWM and lower modes come in...you can push the LED's at FULL BORE for a short time, then dial it back...the FET's just give you a HUGE pipe to push that current thru, the 7135's (that's why there is 8 gives you 8 little 1" waterhoses vs one big 8" main)

Not to insult your intelligence

.22 LR gattling gun?

Sorry, your avatar…

vs a 155....sure...heh

I started college in '75 in engineering, took a Fortran course and loved it. Eventually didn't finish my BS in EE, but went back for CS and got my first job in progamming in '78 at the age of 20. So, been working in software at every possible level for 35 years, more jobs/projects than I can recall. These MCU's are a throw-back to old times for me, but at least it's not assembly language...

While I've been trying to figure these things out I did read a few things on some of the AVR boards about guys writing for the attiny13a in assembly to squeeze more functionality in...that was WAY over my head.

Remember what they were saying back then, while the computer literally took up an entire room? “If the Automobile Industry were progressing at the rate of the Computer Industry a car would cost $20” Man, if they’d only known!
I dropped the programming when my Dad had cancer in ’83, got into the construction side of things and…well, became dumb.

He’s still free of cancer at 85 years old and I’m still dumb….

Been through the IBM deck of cards for writing software on (don't drop the deck! your lines of code will get scrambled), the paper tape thing (yes, I can read binary on paper tape), 8" floppy disks, even bought the original IBM PC with the 4.77 Mhz 8088 (close to state-of-the-art at the time) for $3,500 with a monochrome monitor, single 5 1/4" floppy, DOS 1.0, etc....

This shouldn't be any harder on the LED than any other direct drive driver, if there were a problem it would have been discovered and well-known by now. This is no different than an east-092, it just uses a different MCU that we can write custom firmware for.

Yes, totally agree - no different than a EAST-092 with PWM's -- you get the same pros and cons.

Will even be trying to learn how to flash the driver, should I be scared? lol

I would be if I was the driver.

Capacitor does an amazing job at knocking out nearly all the squeeeee caused by the 9.4kHz firmware... it's barely audible on the bench like that, installed in a light it should be totally gone. Hopefully. :~

Its my understanding and has been documented that a led in low pwm can take a higher current than it can driven fully on. I understand with amc7135 that the current is constant in all modes, but that is because they are current regulators. No matter the voltage or sag of a single li-ion, as long as the voltage is above the vf of the led at that current plus the .12v overhead for the amc7135’s, it will still give its rated current times the number of amc7135’s in any mode.
What I’m not sure about and don’t know exactly if it has been answered here, is if the battery voltage is higher in low modes, less voltage sag with a FET (its basically direct drive with modes from the attiny13). Because if it is that would mean, I’m guessing anyways, That with a higher battery voltage (less voltage sag) direct drive (FET) current would be higher in low modes. Direct drive current is all based on what voltage the supply can give and the other parasitic resistance.
ImA4Wheelr it maybe time to knock the dust off that oscilloscope. :wink:
Forgive me if the question has already been answered. :~

I can hardly understand the language being spoken in this thread but I know I can learn a lot from it if I do my homework. :~

Thanks for leading me to this thread ImA4Wheelr! :slight_smile:

OK, I’m looking at a HX-1175b1 driver. Off memory, it looks just like the HX-1175b in the UF-T90 (SST-90 version) and what I hear is in the Lustfire 3U2?. I does have a blue top coat (instead of black) and it appears to have larger sized “voltage sense resistors” (the “b” has 1206 size). I’m wondering if the are actually “voltage sense resistors” now because of the ciruit lay out. These resistors go between the ground ring and the source pin on the DTU 06N03 FET’s. Changing these resistors directly alters current on the “b” and should on this model too. There are 2 R068 in the resistor bay. In the “b”, the driver delivered 11 amps to an MT-G2 by adding 2 R10 resistors to the bay (If I remember correctly).

So my question is. Are these resistors purely restricting current flow as opposed to being used in a “voltage sensor” circuit. I see no other connections from these resistors and the rest of the driver. Hopefully, you all can picture what I’m talking about. If I can, I will take a couple pictures tomorrow.

EDIT: For those not familar with the HX-1175b, it is a buck driver.

Exactly…a FET is more or less a “solid state switch” when the gate is activated source and drain are connected like a wire the resistance of that wire is the mOhm rating from the spec sheet…the more resistance and more current = heat generated by the chip…but it will push whatever voltage that is on the source thru to the drain, the amc7135’s are regulators the FET is a on of wire (not to insult anyones intelligence)

This isn’t particularly for you…but I too learned alot by watching this video

Again, not to insult anyones intelligence…but to educate {I too was mistaken on what the FET was and how it worked compared to the AMC7135}

Take pictures. Basically the sense resistors must be in the path of the current (of course you’ve already said that these are) and the buck IC must be able to see both sides: in other words if one side is GND (we assume the buck controller is on the same GND) then the other, non-GND side of the sense resistors must have a trace going to the buck IC (preferably a short trace). The buck IC needs to be able to measure voltage drop across the sense resistors.